"Put aside components" - What are R12, D1 and D2 for?

[Subaru_EA82_4EAT_AWD]

Hi, Im currently working on an MS3 + ms3x.
Its the first megasquirt ive had in my hands, so I learning as I go.
I bought it second hand, previous owner never finished it, so Im starting from the beginning of the ms3x/v3.0 hardware manual and checking it over, step by step.

I have fitted the 2can jumpers, the 5 stepper jumpers, and run a 330r lead from IGBTin to top of r26 and fitted links in tach select to vrin, tsel to vrout and igbtout to ign.

So I'm almost ready to test the board, but before I do, i would like to know what R12, D1 and D2 (which were advised to be put aside)are for, they are already fitted (came that way), should they be removed or can they stay?

I will be using an optical CAS, a single coil, either a stepper IAC from the main board or a PWM valve from the ms3x

Also, the components that have a *ms1 only next to them in the BOM, do they need to be taken out or can they stay?

Thanks.

[Matt Cramer]

They're for triggering off the negative terminal of the coil.

[Subaru_EA82_4EAT_AWD]

Ah, thanks!
So can they be left in the board or do they have to come out?

[Subaru_EA82_4EAT_AWD]

...actually I've had a further dig around and found this thread : http://www.msextra.com/forums/viewtopic ... d2#p466431

It seems there are on a separate circuit for the optoisolator which is independent from the VR circuit so I'll leave it as as.


I assume the " *MS1 only" tagged components can stay aswell?
thanks.

[jsmcortina]

Yes. No need to remove them.

Make sure that you only have one selection in each of TSEL and TACHSELECT.

James

[Subaru_EA82_4EAT_AWD]

Thanks guys very helpful.

I aim to complete and test the unit this weekend.

On another topic, Jaycar electronics are a good source for little bits and pieces in Australia if anyone needs lil' things for a project - dropped in and grabbed a Mica insulation kit (enough for 4 mounts) and some nylon washers today:

[DaveEFI]

Odd to supply a mounting kit with no nuts and bolts?

[billr]

Hmm... doesn't seem so odd to me. Those little screws and nuts aren't prone to damage like the micas and plastic washers, and the screws/washers are widely available here (USA). Why have to buy more than I need? (I rarely use nylon screws/nuts, much prefer a "real" fastener and the shoulder-washers!)